TOXICITY OF INSECTICIDES TO COCCINELLA REPANDA THUNBERG (COLEOPTERA: COCCINELLIDAE)

Abstract

Coccinella repanda larvae and adults were tested by topical application to determine their tolerance levels to nine insecticides. Based on 48 hour LD50 values the ascending order of toxicity to larvae was endosulfan, pirimicarb, thiometon, formothion. chlorpyrifos, demeton‐S‐methyl, dimethoate, phos‐phamidon and monocrotophos, and to adults the order was endosulfan, pirimicarb, formothion, chlorpyrifos, thiometon, demeton‐S‐methyl, phosphamidon, dimethoate and monocrotophos. The study was conducted as an aid in developing pest management programmes for Therioaphis trifolii f. maculata and Acrythosiphon kondoi in lucerne as C. repanda is an important predator of the aphids. Copyright © 1980, Wiley Blackwell. All rights reserved